Risk and survival of patients with non-small cell lung cancer and pre-existing autoimmune disorders receiving immune checkpoint blockade therapy: Survival analysis with inverse probability weighting from a nationwide, multi-institutional, retrospective study (NEJ047).

BACKGROUND: The risk and survival of patients with non-small cell lung cancer (NSCLC) with pre-existing autoimmune disorders (AIDs) receiving immune checkpoint blockade (ICB) therapy have not been clearly established. PATIENTS AND METHODS: This multi-institutional, retrospective cohort study was conducted in collaboration with 20 centers in Japan. RESULTS: In total, 229 patients with advanced or recurrent NSCLC and pre-existing AID, with or without ICB treatment from January 2010-February 2020, were included and analyzed. Among 69 patients who received ICB, 2 received two lines of ICBs with a total of 71 ICB treatments; 57 (80.3 %) and 14 (19.7 %) patients received ICB monotherapy and combination therapy, respectively. AID flares were observed in 18 patients (25.4 %, 95 % confidence interval [CI], 15.8-37.1 %) receiving ICB. AID exacerbations were more likely when NSCLC was diagnosed less than 1 year after the AID diagnosis (odds ratio 5.26 [95 % CI, 1.40-21.61]; P = 0.016). Immune-related adverse events were observed in 32 patients (45.1 %, 95 % CI, 33.2-57.3 %); 17 had grade 3 or higher. The safety profile of combination immunotherapy was not significantly different from that of the monotherapy. After inverse probability weighting, the use of ICB prolonged survival (hazard ratio 0.43 [95 % CI, 0.26-0.70]; P = 0.0006). CONCLUSIONS: These findings revealed a novel risk factor for AID flares following ICB treatment, that is the diagnosis of NSCLC within 1 year of AID diagnosis, and showed that ICBs may improve survival in this population. These results support the utilization of ICB in patients with NSCLC and pre-existing AID.

A case of hepatoid adenocarcinoma of the lung harboring KRAS G12C responded favorably to sotorasib.

Hepatoid adenocarcinoma of the lung is a rare variant of adenocarcinoma. We describe a case of hepatoid adenocarcinoma of the lung that harbored KRAS G12C and responded favorably to sotorasib. A man in his 70s was found to have an abnormality on his chest X-ray. He underwent right middle lobectomy, and a pathological examination of the surgical specimen showed conventional invasive adenocarcinoma with highly focal hepatoid adenocarcinoma. He received chemoradiotherapy and concurrent radiation, followed by durvalumab for postoperative recurrence. After three doses of durvalumab, he reported feeling short of breath. A computed tomography scan showed emerging broad consolidation in the right lower lobe. Transbronchial lung biopsy specimens from the consolidation showed hepatoid adenocarcinoma harboring KRAS G12C mutation. Therefore, he was started on sotorasib 960 mg daily. Eight days later, a computed tomography scan showed that the area of consolidation had reduced in size. Progressive disease was detected after 42 days of treatment with sotorasib. The patient died 1 month after cessation of sotorasib and 3 months after postoperative recurrence. We have encountered what we believe to be the first case of hepatoid adenocarcinoma of the lung with KRAS G12C mutation that responded favorably to treatment with sotorasib.

Pulmonary Artery Aneurysm in a Patient with Nontuberculous Mycobacteria Infection.

Nontuberculous mycobacterial (NTM) infection sometimes leads to the development of pulmonary artery aneurysm (PAA), a rare but life-threatening complication. We herein report a 64-year-old woman with a history of NTM infection who presented with severe hemoptysis. Computed tomography revealed a ruptured PAA, which was treated successfully with pulmonary artery embolization. Subsequent right total pneumonectomy was performed to control infection. This case emphasizes the need to consider PAA in patients with NTM infection who present with hemoptysis. Early detection and appropriate management are critical for preventing this fatal complication.

Deep convolutional neural network for differentiating between sarcoidosis and lymphoma based on [18F]FDG maximum-intensity projection images.

OBJECTIVES: To compare the [18F]FDG PET/CT findings of untreated sarcoidosis and malignant lymphoma (ML) and develop convolutional neural network (CNN) models to differentiate between these diseases using maximum intensity projection (MIP) [18F]FDG PET images. METHODS: We retrospectively collected data on consecutive patients newly diagnosed with sarcoidosis and ML who underwent [18F]FDG PET/CT before treatment. Two nuclear radiologists reviewed the images. CNN models were created using MIP PET images and evaluated with k-fold cross-validation. The points of interest were visualized using gradient-weighted class activation mapping (Grad-CAM). RESULTS: A total of 56 patients with sarcoidosis and 62 patients with ML were included. Patients with sarcoidosis had more prominent FDG accumulation in the mediastinal lymph nodes and lung lesions, while those with ML had more prominent accumulation in the cervical lymph nodes (all p < 0.001). For the mediastinal lymph nodes, sarcoidosis patients had significant FDG accumulation in the level 2, 4, 7, and 10 lymph nodes (all p < 0.01). Otherwise, the accumulation in ML patients tended to be in the level 1 lymph nodes (p = 0.08). The CNN model using frontal and lateral MIP images achieved an average accuracy of 0.890 (95% CI: 0.804-0.977), a sensitivity of 0.898 (95% CI: 0.782-1.000), a specificity of 0.907 (95% CI: 0.799-1.000), and an area under the curve of 0.963 (95% CI: 0.899-1.000). Grad-CAM showed that the model focused on the sites of abnormal FDG accumulation. CONCLUSIONS: CNN models based on differences in FDG accumulation sites archive high performance in differentiating between sarcoidosis and ML. CLINICAL RELEVANCE STATEMENT: We developed a CNN model using MIP images of [18F]FDG PET/CT to distinguish between sarcoidosis and malignant lymphoma. It achieved high performance and could be useful in diagnosing diseases with involvement across organs and lymph nodes. KEY POINTS: • There are differences in FDG distribution when comparing whole-body [18F]FDG PET/CT findings in patients with sarcoidosis and malignant lymphoma before treatment. • Convolutional neural networks, a type of deep learning technique, trained with maximum-intensity projection PET images from two angles showed high performance. • A deep learning model that utilizes differences in FDG distribution may be helpful in differentiating between diseases with lesions that are characteristically widespread among organs and lymph nodes.

Local nasal immunotherapy with birch pollen-galactomannan conjugate-containing ointment in mice and humans.

BACKGROUND: Allergen immunotherapy (AIT) is the only disease-modifying treatment for immunoglobulin (Ig) E-mediated allergy. Owing to the high prevalence and early onset of hay fever and pollen-food allergy syndrome (PFAS), a safer and simpler treatment method than conventional AIT is needed. To develop a local nasal immunotherapy using an ointment containing hypoallergenic pollen and assess its efficacy in mice and healthy humans. METHODS: Hypoallergenicity was achieved by combining pollen and galactomannan through the Maillard reaction to create birch pollen-galactomannan conjugate (BP-GMC). The binding of galactomannan to Bet v 1 was confirmed using electrophoresis and Western blotting (WB). Binding of specific IgE antibodies to BP-GMC was verified using enzyme-linked immunosorbent assay (ELISA) and basophil activation test (BAT). The localization of BP-GMC absorption was confirmed using a BALB/c mouse model. BP-GMC mixed with white petrolatum was intranasally administered to 10 healthy individuals (active drugs, 8; placebo, 2) for 14 days. RESULTS: In electrophoresis and WB, no 17-kDa band was observed. In ELISA and BAT, BP-GMC did not react to specific IgE but was bound to IgA and IgG. In the mouse model, BP-GMC was detected in nasopharyngeal-associated lymphoid tissues. In the active drug group, the salivary-specific IgA level significantly increased on day 15 (p = 0.0299), while the serum-specific IgG level significantly increased on day 85 (p = 0.0006). CONCLUSIONS: The BP-GMC ointment rapidly produced antagonistic antibodies against IgE; it is safe and easy to use and might serve as a therapeutic antigen for hay fever and PFAS.

[HUMIDIFIER LUNG WITH ORGANIZING PNEUMONIA DETECTED BY BRONCHOSCOPY: A CASE REPORT].

A 58-year-old man presented with dyspnea on exertion and diffuse ground-glass opacities with mosaicism on chest computed tomography in April 201X. A transbronchial lung biopsy revealed organizing pneumonia and lymphocytic infiltration, and steroids were administered. During steroid tapering, the shortness of breath and ground-glass opacities recurred, and a transbronchial lung re-biopsy revealed organizing pneumonia without a granuloma again. Based on the clinical history, imaging features, and amount of humidifier usage, hypersensitivity pneumonitis caused by a humidifier was suspected. The inhalation challenge test was considered positive, and the diagnosis was confirmed. There have been some reports of unidentified granuloma in patients with humidifier lungs. Therefore, this case suggests that humidifier lung should be considered as a possibility even if pathological examination does not reveal granulomas and inflammatory changes such as organizing pneumonia are the only findings.

Risk factors and interventions for developing recurrent pneumonia in older adults.

Background: Pneumonia is common among older adults and often recurrent. Several studies have been conducted on the risk factors for pneumonia; however, little is known about the risk factors for recurrent pneumonia. This study aimed to identify the risk factors for developing recurrent pneumonia among older adults and to investigate methods of prevention. Methods: We analysed the data of 256 patients aged 75 years or older who were admitted for pneumonia between June 2014 and May 2017. Moreover, we reviewed the medical records for the subsequent 3 years and defined the readmission caused by pneumonia as recurrent pneumonia. Risk factors for recurrent pneumonia were analysed using multivariable logistic regression analysis. Differences in the recurrence rate based on the types and use of hypnotics were also evaluated. Results: Of the 256 patients, 90 (35.2%) experienced recurrent pneumonia. A low body mass index (OR: 0.91; 95% CI: 0.83‒0.99), history of pneumonia (OR: 2.71; 95% CI: 1.23‒6.13), lung disease as a comorbidity (OR: 4.73; 95% CI: 2.13‒11.60), taking hypnotics (OR: 2.16; 95% CI: 1.18‒4.01) and taking histamine-1 receptor antagonist (H1RA) (OR: 2.38; 95% CI: 1.07‒5.39) were risk factors. Patients taking benzodiazepine as hypnotics were more likely to experience recurrent pneumonia than patients not taking hypnotics (OR: 2.29; 95% CI: 1.25-4.18). Conclusion: We identified several risk factors for recurrent pneumonia. Among them, restricting the use of H1RA and hypnotics, in particular benzodiazepines, may be useful in preventing the recurrence of pneumonia in adults aged 75 years or older.

COVID-19 Pneumonia Followed by Anti-signal Recognition Particle Antibody-positive Fibrosing Interstitial Lung Disease.

Coronavirus disease 2019 (COVID-19) pneumonia is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and is frequently accompanied by various sequelae. Interstitial lung diseases (ILDs) are observed in COVID-19 pneumonia patients after recovery, probably due to persistent inflammation in the lungs. We herein report a case of ILD with anti-signal recognition particle antibodies following severe COVID-19 pneumonia. The patient was diagnosed with ILD three months after COVID-19 pneumonia. Although the exact mechanism is unknown, the autoantibody-induced immune response might have been the pulmonary fibrosis trigger in this patient.

Primary bronchial schwannoma: A case report.

RATIONALE: Bronchial schwannomas are extremely rare among the benign tracheobronchial tumors and little are known about its epidemiology and optimal clinical management. Here, we report a case of bronchial schwannoma in a young Japanese man and clinical implications about epidemiology, symptom, diagnosis, and treatment of bronchial schwannoma. PATIENTS CONCERN: A 37-year-old man visited our department with a nodule incidentally found on his chest radiograph during a routine medical checkup. DIAGNOSIS: The tumor was diagnosed as a bronchial schwannoma after pathological evaluation. Microscopically, the tumor consisted of spindle cell proliferation characterized by an alternating highly ordered cellular Antoni A component with occasional nuclear palisading and a loose myxoid Antoni B component. Tumor cells were immunoreactive for S100 but not for smooth muscle actin or KIT. INTERVENTIONS: A video-assisted right middle and lower bilobectomy was performed. OUTCOME: He remains under observation without recurrence. LESSONS: In our review, many reports have come from Asian countries. Bronchial schwannoma can occur within a wide range of age groups and in both men and women. No difference in incidence was observed between right and left bronchial tree. Bronchial schwannoma is sometimes difficult to differentiate from malignant diseases. We should include bronchial schwannoma as one of the differential diagnoses of primary bronchial tumors.

Association of SARS-CoV-2 RNA Copy Number with the COVID-19 Mortality Rate and Its Effect on the Predictive Performance of Mortality in Severe Cases.

Factors associated with mortality are important in the treatment of coronavirus disease 2019 (COVID-19). Polymerase chain reaction (PCR) is the gold standard for diagnosing COVID-19, which reflects the viral load in the upper respiratory tract. In total, 523 patients were enrolled in this study; of them, 441 and 75 patients underwent PCR testing of nasopharyngeal swabs and sputum samples, respectively, within 20 days from onset of COVID-19. We investigated the association between RNA copy number and the COVID-19 severity and mortality rate and its effect on the predictive performance for severity and mortality. RNA copy numbers in nasopharyngeal swabs were higher in the non-survivor group than in the survivor group. Multivariate logistic regression analysis identified that the high RNA copy number (≥9 log10 /swab) in nasopharyngeal swabs was a factor associated with mortality (odds ratio, 4.50; 95% confidence interval, 1.510-13.100; P = 0.008). Furthermore, adding RNA copy number (≥9 log10 /swab) in severe cases, adjusted by duration from onset to PCR, improved mortality predictive performance based on known factors. The RNA copy number is a factor associated with the mortality of patients with COVID-19 and can improve the predictive performance of mortality in severe cases.

Successful diagnosis of humidifier lung by individual provocation test to a responsible environment, a case report.

A 52-year-old woman presented with repeating episodes of pneumonia which spontaneously resolved after hospitalization. Hypersensitivity pneumonitis was suspected, but the causative antigen was not determined whether the parakeets she kept or the humidifier she owned was causative exposure. To identify which exposure is culprit, individual provocation test to a responsible environment was sequentially conducted. First, a home-returning provocation test to the parakeet was negative. Contrarily, the humidifier provocation test to her own humidifier was positive for symptoms, radiological changes, and inflammatory responses in blood test. Finally, she was diagnosed as having humidifier lung. When several antigens are suspected to be the causative agents for hypersensitivity pneumonitis, a step-by-step provocation tests is useful.

Evaluation of Respiratory Resistance as a Predictor for Oral Appliance Treatment Response in Obstructive Sleep Apnea: A Pilot Study.

The aim of this study was to determine the utility of respiratory resistance as a predictor of oral appliance (OA) response in obstructive sleep apnea (OSA). Twenty-seven patients with OSA (mean respiratory event index (REI): 17.5 ± 6.5 events/h) were recruited. At baseline, the respiratory resistance (R20) was measured by impulse oscillometry (IOS) with a fitted nasal mask in the supine position, and cephalometric radiographs were obtained to analyze the pharyngeal airway space (SPAS: superior posterior airway space, MAS: middle airway space, IAS: inferior airway space). The R20 and radiographs after the OA treatment were evaluated, and the changes from the baseline were analyzed. A sleep test with OA was carried out using a portable device. The subjects were divided into Responders and Non-responders based on an REI improvement ≥ 50% from the baseline, or REI < 5 after treatment, and the R20 reduction rate between the two groups were compared. The subjects comprised 20 responders and 7 non-responders. The R20 reduction rate with OA in responders was significantly greater than it was in non-responders (14.4 ± 7.9 % versus 2.4 ± 9.8 %, p < 0.05). In responders, SPAS, MAS, and IAS were significantly widened and R20 was significantly decreased with OA (p < 0.05). There was no significant difference in non-responders (p > 0.05). A logistic multiple regression analysis showed that the R20 reduction rate was predictive for OA treatment responses (2% incremental odds ratio (OR), 24.5; 95% CI, 21.5-28.0; p = 0.018). This pilot study confirmed that respiratory resistance may have significant clinical utility in predicting OA treatment responses.

Predictors associated with clinical improvement of SARS-CoV-2 pneumonia.

BACKGROUND: There are few agents that have been proven effective for COVID-19. Predicting clinical improvement as well as mortality or severity is very important. OBJECTIVES: This study aimed to investigate the factors associated with the clinical improvement of COVID-19. METHODS: Overall, 74 patients receiving treatment for COVID-19 at Tokyo Medical and Dental University Hospital from April 6th to May 15th, 2020 were included in this study. Clinical improvement was evaluated, which defined as the decline of two levels on a six-point ordinal scale of clinical status or discharge alive from the hospital within 28 days after admission. The clinical courses were particularly investigated and the factors related to time to clinical improvement were analyzed with the log-rank test and the Cox proportional hazard model. RESULTS: Forty-nine patients required oxygen support during hospitalization, 22 patients required invasive mechanical ventilation, and 5 patients required extracorporeal membrane oxygenation. A total of 83% of cases reached clinical improvement. Longer period of time from onset to admission (≥10 days) (HR, 1.057; 95% CI, 1.002-1.114), no hypertension (HR, 2.077; 95% CI, 1.006-4.287), and low D-dimer levels (<1 µg/ml) (HR, 2.372; 95% CI, 1.229-4.576) were confirmed to be significant predictive factors for time to clinical improvement. Furthermore, a lower SARS-CoV-2 RNA copy number was also a predictive factor for clinical improvement. CONCLUSIONS: Several predictors for the clinical improvement of COVID-19 pneumonia were identified. These results may be important for the management of COVID-19 pneumonia.

Efficacy of multidisciplinary team approach with extracorporeal membrane oxygenation for COVID-19 in a low volume ECMO center.

Veno-venous extracorporeal membrane oxygenation (VV ECMO) is an effective and proven adjunct support for various severe respiratory failures requiring invasive mechanical ventilation and cardiovascular support. In response to the rapidly increasing number of COVID-19 patients in Japan, we launched an ECMO support team comprised of multidisciplinary experts including physicians, nurses, perfusionists, and bioethicists in preparation for the threat of a pandemic. From April 2 to July 15, 2020, Tokyo Medical and Dental University hospital treated 104 PCR confirmed COVID-19 patients. Among those, 34 patients were admitted to intensive care unit (ICU) and 5 patients required VV ECMO. All management related to ECMO was decided by the ECMO support team in addition to participation of the ECMO support team in daily multidisciplinary rounds in the ICU. Median age was 54 years old. Duration from onset to mechanical ventilation (MV) and MV to ECMO were 8 and 7 days, respectively. Four patients (80%) were successfully weaned off from ECMO. One patient died after 81 days of ECMO run. Four patients were discharged and recovered to their prehospital quality of life without major disability. We achieved a high survival rate using ECMO in our low volume ECMO institution during the COVID-19 pandemic. Multidisciplinary decision-making and a team approach for the unclear pathology with an emerging infectious disease was effective and contributed to the survival rate.

MuLBSTA score is a useful tool for predicting COVID-19 disease behavior.

BACKGROUND: The prediction of COVID-19 disease behavior in the early phase of infection is challenging but urgently needed. MuLBSTA score is a scoring system that predicts the mortality of viral pneumonia induced by a variety of viruses, including coronavirus, but the scoring system has not been verified in novel coronavirus pneumonia. The aim of this study was to validate this scoring system for estimating the risk of disease worsening in patients with COVID-19. METHODS: This study included the patients who were treated between April 1 st and March 13 th , 2020. The patients were classified into mild, moderate, and severe groups according to the extent of respiratory failure. MuLBSTA score was applied to estimate the risk of disease worsening in each severity group and we validated the utility of the scoring system. RESULTS: A total of 72 patients were analyzed. Among the 46 patients with mild disease, 17 showed disease progression to moderate or severe disease after admission. The model showed a sensitivity of 100% and a specificity of only 34.5% with a cut-off value of 5 points. Among the 55 patients with mild or moderate disease, 6 deteriorated to severe disease, and the model showed a sensitivity of 83.3% and a specificity of 71.4% with a cut-off value of 11 points. CONCLUSIONS: This study showed that MuLBSTA score is a potentially useful tool for predicting COVID-19 disease behavior. This scoring system may be used as one of the criteria to identify high-risk patients worsening to life-threatening status.

Notable response to nivolumab during the treatment of SMARCA4-deficient thoracic sarcoma: a case report.

SMARCA4-deficient thoracic sarcoma is a rare tumor typically presenting as a mediastinal mass. The prognosis is estimated to be poor, and no effective treatment has been established. We present a case of a 76-year-old man who was diagnosed with SMARCA4-deficient thoracic sarcoma. The provisional diagnosis was carcinoma of unknown primary but subsequently corrected to SMARCA4-deficient thoracic sarcoma based on the panel-based cancer gene screening and immunohistochemistry. Cytotoxic chemotherapy as the first- and second-line did not reveal enough therapeutic effects but third-line therapy using nivolumab showed marked tumor regression, which was sustained. This is the first case report of SMARCA4-deficient thoracic sarcoma showing a good response to nivolumab. Immune checkpoint inhibitor might be therapeutic candidates for this type of tumor.

A New Feature with the Potential to Detect the Severity of Obstructive Sleep Apnoea via Snoring Sound Analysis.

The severity of obstructive sleep apnoea (OSA) is diagnosed with polysomnography (PSG), during which patients are monitored by over 20 physiological sensors overnight. These sensors often bother patients and may affect patients' sleep and OSA. This study aimed to investigate a method for analyzing patient snore sounds to detect the severity of OSA. Using a microphone placed at the patient's bedside, the snoring and breathing sounds of 22 participants were recorded while they simultaneously underwent PSG. We examined some features from the snoring and breathing sounds and examined the correlation between these features and the snore-specific apnoea-hypopnea index (ssAHI), defined as the number of apnoea and hypopnea events during the hour before a snore episode. Statistical analyses revealed that the ssAHI was positively correlated with the Mel frequency cepstral coefficients (MFCC) and volume information (VI). Based on clustering results, mild snore sound episodes and snore sound episodes from mild OSA patients were mainly classified into cluster 1. The results of clustering severe snore sound episodes and snore sound episodes from severe OSA patients were mainly classified into cluster 2. The features of snoring sounds that we identified have the potential to detect the severity of OSA.

[A Case of Pulmonary Enteric Adenocarcinoma with Soleus Muscle Metastasis].

Pulmonary enteric adenocarcinoma is a unique pulmonary adenocarcinoma subtype and has histopathological findings that are similar to those of colorectal adenocarcinoma. A man in his 50s visited our hospital because of discomfort in his right lower leg for the last 9 months. Imaging studies revealed a mass in his right soleus muscle, and needle biopsy was performed. Histological findings revealed adenocarcinoma, and immunohistochemical staining showed that the tumor cells were positive for CK20 and CDX-2. The tumor was first suspected to be metastasis of gastrointestinal malignant tumors. FDG-PET/CT showed increased FDG uptake in the right soleus muscle mass and presented with increased FDG uptake in a right upper lobe mass and right mediastinum lymphadenopathy. There were no findings in other organs. Scraping cytology of a transbronchial biopsy indicated adenocarcinoma. Upper and lower gastrointestinal endoscopy showed no findings of malignancy. He was finally diagnosed with pulmonary enteric adenocarcinoma(cT3N2M1b, Stage ⅣA). Treatment with cisplatin(CDDP), pemetrexed( PEM), and bevacizumab(BEV) was initiated. After 4 courses of the regimen, the tumor was partially reduced, and the patient showed stable disease(SD).

Effect of jaw-opening exercise on prevention of temporomandibular disorders pain associated with oral appliance therapy in obstructive sleep apnea patients: A randomized, double-blind, placebo-controlled trial.

PURPOSE: There are no studies on the prevention of temporomandibular joint and/or masticatory muscle pain (TMD pain) associated with oral appliance (OA) therapy in patients with obstructive sleep apnea (OSA). The aim of this study was to determine the effect of jaw-opening exercise on TMD pain associated with OA therapy in OSA patients. METHODS: Twenty-five OSA patients without pain-related TMD were consecutively enrolled into a two-arm, randomized, double-blind, placebo-controlled trial. One group performed jaw-opening exercise (JE, n=13), and the other group performed placebo exercise (PE, n=12) for 1-month, and had started 2-weeks prior to insertion of an adjustable OA. TMD sign using the Research Diagnostic Criteria for Temporomandibular Disorders and TMD pain intensity using a visual analog scale (VAS) in the morning and daytime were evaluated at baseline (pre-exercise) and at 2-weeks, 1-month, and 3-months after OA insertion. RESULTS: Pain-related TMD was not observed in the JE-group at all evaluation periods, although one subject in the PE-group was diagnosed with arthralgia at the 1-month evaluation. The JE-group showed lower morning and daytime VAS scores than the those of the PE-group at all evaluation periods, and significant group differences were found in terms of chewing pain and jaw-opening pain in the morning at the 1-month evaluation, and of jaw-opening pain during daytime at the 3-month evaluation (P<0.05). CONCLUSIONS: Within the limitations of the study, jaw-opening exercise prior to OA therapy reduced the risk of TMD pain associated with OA use. Therefore, jaw-opening exercise may contribute to the prevention of TMD pain.